In general, I think so. Though I have only met one (confirmed) INFJ before. She was probably the first person in high school I was able to have an awesome conversation with. She got someone to open up to and I got someone willing to listen to some of my craziness, so I think it's potentially a good dynamic

I could see how some problems could come up if I was pushed to be more socioemotionally serious, or if I started insisting on "lightening/loosening up," so that could create a better understanding, or explosions (the bad kind).
It really depends.... I do think they are very similar (because I'm biased like that), but in general:
From the INTP: expect more quiet evenings at home reading books/playing video games together, a cute sort of sillyness, messiness but with the occasional extreme perfectionism, more random emotional outbursts, more insistence that things "make sense"
From the ENTP: expect more random outings or not-so-quiet evenings at home (explosions, but the good kind), a "charming" sort of crazy, a general scatteredness, more resistence to a controlled stability, more concern with their "audience"
...and things that go along with these things, and things already included in the NTP part.
Actually, the part about the ENTPs wanting action more
almost sums up the difference completely
So the question is of which flavor of crazy do you prefer?